source: asp3_tinet_ecnl_rx/trunk/musl-1.1.18/src/legacy/getusershell.c@ 337

#define _GNU_SOURCE
#include <stdio.h>
#include <unistd.h>

static const char defshells[] = "/bin/sh\n/bin/csh\n";

static char *line;
static size_t linesize;
static FILE *f;

void endusershell(void)
{
        if (f) fclose(f);
        f = 0;
}

void setusershell(void)
{
        if (!f) f = fopen("/etc/shells", "rbe");
        if (!f) f = fmemopen((void *)defshells, sizeof defshells - 1, "rb");
}

char *getusershell(void)
{
        ssize_t l;
        if (!f) setusershell();
        if (!f) return 0;
        l = getline(&line, &linesize, f);
        if (l <= 0) return 0;
        if (line[l-1]=='\n') line[l-1]=0;
        return line;
}